The tower members are designed as angle section. Prior to the design process the convincing site investigation and Envoirmental impact assessment data has to to collected through various modes via Electronic or Print media. The desired safety factors has been actuated contemplating the selected location i. The various factors including envoirmental and materials used for the structure is also be considered. The foundation detailing is chosen keeping in consideration the geotechnical investigation data.
Pro The load calculations were performed manually but the analysis and design results were obtained through STAAD. At all stages, the effort is to provide optimally safe design along with keeping the economic considerations. Pro , Non- linear irregularities. The tower is to be located in II.
Safe and economic In the present section, the tower has been detailed for its design of steel transmission tower using the software tool location, type and kind of constituent members. The height of the tower is 25 m. The Introduction to Tower number of cables supported by this tower is 7. A tower is a freely standing self commonly used for T.
The free standing towers In developed countries the environmental impact of the for power transmission have arms to both the sides of the traditional transmission towers is no longer accepted. Currently available design solutions with acceptable appearance are not employed in the developing countries, mainly for cost reasons. In the developing countries the use of the traditional lattice transmission towers will continue employing steel angles.
A comparison of the available design specifications for steel angles in transmission towers is presented. Generally towers are made up of a material called steel. Steel towers short, medium and tall are normally used for the following purposes: i Electric power transmission ii Microwave transmission for communication iii Radio transmission short and medium wave wireless iv Television transmission v Satellite reception vi Air traffic control vii Flood light stand viii Metrological measurements Fig.
GUYED TOWERS xi Over head tanks Guyed towers are hinged to the base, and are supported by Further classification of towers depending upon their heights guy wires attached to it at various levels, to transmit the is as follows: wind forces to the ground. Due to this reason, guyed tower The height of towers for electric power transmission may of the same height is much lighter than a self- supporting vary from 10 to 45m while those for flood lights in stadiums tower.
However, it requires much larger space in plan, to The height of television towers may vary from m to accommodate the placement of guy ropes. Guyed towers are m while for those for radio transmission and communication mostly known as masts, having three or four legs and networks the height may vary from 50 to m. Depending upon the size and type of loading, towers are grouped into two heads: a Towers with large vertical loads b Towers with mainly horizontal wind loads Towers with large vertical loads such as those of over head water tanks, oil tanks, metrological instrumentation towers etc.
The towers, falling under the second category and subjected predominantly to wind loads, may be classified in to two types: 1 Self-supporting towers 2 Guyed towers Fig. These are generally square in plan and are loads, are called lattice towers.
Such towers are square or supported by four legs, fixed to the base. Rolled Steel long leg equal angles back to back depending upon the requirement. Concrete Base There are ten types of bracing systems for a lattice tower 5. Footing configuration. Those ten types are as follows: Parameters of the tower 1. Single diagonal bracings: This is the simplest form of 1. The building lies in Seismic Zone IV bracing.
The wind shear at any level is shared by the single 2. The factor of safety of the tower is 1. Such bracing is used for towers upto 3.
The height of the tower is The base width of the tower is 3. X-X bracing: This is a double diagonal system without 5. The top width of the tower is 1. The Flange width in the tower is 2. The bearing capacity of the soil assumed to be 3. Such bracings are quite rigid, and may Analysis model for tower be used for towers up to 50m height. The structure is Number of members: statically indeterminate.
The horizontal members are Number of joints: redundant members and carry only nominal stresses. Loading: Self weight, Wind load, 4. Pro head room is required. The structure is statically determinate. Such bracing can be used for towers of 50 to m height.
In most of the transmission line towers, the lower panels is either K- or Y- braced and upper panels are X-braced or XB- braced. X B X bracing: This is a combination XX and XB bracing where horizontal members are provided only at the level of crossing of diagonals. The structure is statically indeterminate. However, the length of the diagonal is reduced. The system is suitable for towers 50 to m height.
W-bracing: This system uses a number of overlapping diagonals. The system is statically indeterminate. However, the effective length of diagonals is reduced the system is quite rigid and may be used for towers of 50 to 20m height. Y-bracing: This system gives larger head room can be used for lower panels. The system is statically determinate. In most of the transmission line towers, lower panels are either Y-braced on k-braced and upper panels are X-B braced or X-braced.
Arch bracing:Ssuch a bracing can be adopted for wider showing stresses panels. This system also provides greater head room. Subdivided V-bracing: Such a bracing are used for tall towers of communication systems, radio and TV transmission etc; for heights between 50 to m. Updated and expanded to reflect all the important developments that have occurred in the field over the past decade, this Fourth Edition of the classic text provides you with more of the detailed, up-to-the-minute technical information and expert guidance you need to make optimum use of this incredibly versatile material for building construction.
Wei-Wen Yu and Roger LaBoube, respected authorities in the field, draw upon decades of experience in cold-formed steel design, research, teaching, and development of design specifications to provide guidance on all practical aspects of cold-formed steel design for manufacturing, civil engineering, and building applications. Throughout the book, they describe the structural behavior of cold-formed steel members and connections from both the theoretical and experimental perspectives, and discuss the rationale behind the AISI and North American design provisions.
It is also an excellent advanced text for college students and researchers in structural engineering, architectural engineering, construction engineering, and related disciplines. The authors address a myriad of topics, covering both traditional and innovative approaches to analysis, design, and rehabilitation. The second edition has been expanded and reorganized to be more informative and cohesive.
It also follows the developments that have emerged in the field since the previous edition, such as advanced analysis for structural design, performance-based design of earthquake-resistant structures, lifecycle evaluation and condition assessment of existing structures, the use of high-performance materials for construction, and design for safety. Additionally, the book includes numerous tables, charts, and equations, as well as extensive references, reading lists, and websites for further study or more in-depth information.
Emphasizing practical applications and easy implementation, this text reflects the increasingly global nature of engineering, compiling the efforts of an international panel of experts from industry and academia.
This is a necessity for anyone studying or practicing in the field of structural engineering. New to this edition Fundamental theories of structural dynamics Advanced analysis Wind and earthquake-resistant design Design of prestressed concrete, masonry, timber, and glass structures Properties, behavior, and use of high-performance steel, concrete, and fiber-reinforced polymers Semirigid frame structures Structural bracing Structural design for fire safety.
All Rights Reserved.
0コメント